[CodeGen] Constify changeTypeToInteger

[nextsilicon-itay-bookstein]

Summary

Surrounding methods are const, seems to be an oversight.

Signed-off-by: Itay Bookstein <[e-mail]>

[bogner]

lgtm

llvm/include/llvm/CodeGen/ValueTypes.h

EVT changeVectorElementType(EVT EltVT) const {
         return getSimpleVT().changeVectorElementType(EltVT.getSimpleVT());
       }
       return changeExtendedVectorElementType(EltVT);
     }
 
     /// Return the type converted to an equivalently sized integer or vector
     /// with integer element type. Similar to changeVectorElementTypeToInteger,
     /// but also handles scalars.
-    EVT changeTypeToInteger() {
+    EVT changeTypeToInteger() const {
       if (isVector())
         return changeVectorElementTypeToInteger();
 
       if (isSimple())
         return getSimpleVT().changeTypeToInteger();
       return changeExtendedTypeToInteger();
     }